MITRA Forum Question Details

​I assume you are referring to the use of solvents and/or diluents here? Acrylic emulsion paints can be thinned typically using water while oil paints are GENERALLY thinned using a solvent (something like mineral spirits or turpentine). Is this the kind of information you are after?

If your question refers to the ​consistency of paints straight from the tube or jar, there are a few reasons why some are relatively thin while others are stiff. Paint that has a relatively low proportion of solids to vehicle can be runny.

Ideally, the solid ingredient in oil paint is mostly pigment, which gives paint its color. In craft-grade and scholastic-grade acrylic paints, some of the pigment might be replaced with an inert filler like chalk or, in the case of oil paints, waxy fillers that cause some of the oil vehicle to gel. There are also liquid acrylic colors (sometimes called 'fluid acrylics') that are specially formulated to have a thin body, with the same strong color as tube colors.

Oil paints can also look runny if some vehicle separates out in storage. When the tube is opened, some oil might run out, but the remainder of the tube will have a normal consistency.

In addition we have loads of information on this in our resources section in addition to helpful links listed at the end of each document. You should consult the sections on "oil paint" and "acrylic" in the Paint Mediums and Additives document which can be found here.